Unity Integration

Use the Stash Pay Unity integration to add checkout to your iOS and Android projects. This guide shows you how to install the Unity SDK, configure deep links, and display the Stash checkout in your game.

Before you begin

This guide applies to both iOS and Android Unity projects. The integration process is identical for both platforms, and the Unity SDK handles platform-specific tasks automatically.

Before integrating Stash Pay into your Unity project, ensure you are familiar with how the Stash Pay system works, including the end-to-end checkout flow. You should already know how to generate checkout links and handle purchase verification securely on your game server before proceeding with Unity integration.

We recommend reviewing the following articles first:

• High-level flow: Overview of the checkout flow and steps to obtain your API key.
• Integrating Stash Pay: How to generate a checkout link and handle webhook events for integration.

Unity SDK Requirements

• Unity 2022.3 and above recommended.
• iOS 12+ / Android 11+

Set up

Install the Stash Unity SDK before implementing the checkout flow.

Configure deeplinks

Configuring deeplinks is highly recommended for a seamless payment experience even though it is not strictly required for in-app checkout with Stash Pay. Deeplink support enables Stash Pay to redirect players back into your game after a browser-based checkout or when certain payment methods open external pages by necessity.

To set up deeplinking:

• Follow the Unity Deep Linking guide to configure your preferred deeplink schema in your Unity project.
• Register and set up the same deeplink schema in Stash Studio so that Stash Pay can redirect players to your game when necessary.

This approach ensures that whenever Stash needs to return a user from an external checkout flow, they are brought directly back into your app with the correct context.

Using In-app Checkout

Call StashPayCard.Instance.OpenCheckout() to present the Stash Pay checkout using a native card dialog. The Stash SDK automatically detects the platform (iOS or Android) and device type (phone or tablet), choosing the best experience and layout for the user.

using StashPopup;

public class MyStore : MonoBehaviour
{
    void PurchaseItem(string checkoutUrl)
    {
        // checkoutUrl is a Stash Pay URL generated on your game backend.
        StashPayCard.Instance.OpenCheckout(
            checkoutUrl,
            dismissCallback: OnCheckoutDismissed,
            successCallback: OnPaymentSuccess,
            failureCallback: OnPaymentFailure
        );
    }
    
    void OnCheckoutDismissed()
    {
        // User closed the dialog, do nothing or handle accordingly.
    }
    
    void OnPaymentSuccess()
    {
        // Payment was completed
        // Trigger purchase validation on the server.
        VerifyAndGrantPurchase();
    }
    
    void OnPaymentFailure()
    {
        // Payment failed - show error to user
        ShowErrorMessage("Payment could not be processed");
    }
}

Using Browser Mode

Stash Popup also supports launching the checkout in the system browser using SFSafariViewController on iOS or Chrome Custom Tabs on Android, instead of showing it within the in-game popup. You can enable this behavior directly in your code, or dynamically manage it for specific user segments via settings in Stash Studio.

void OpenInBrowser(string url)
{
    // Enable browser mode
    StashPayCard.Instance.ForceWebBasedCheckout = true;
    
    // Opens in Safari/Chrome instead of card
    // successCallback and failureCallback are not available for the browser mode.
    StashPayCard.Instance.OpenCheckout(url, OnDismiss);
    
    // Restore default mode
    StashPayCard.Instance.ForceWebBasedCheckout = false;
}

Unity Editor Testing

The plugin includes a Unity editor extension that allows you to test Stash Pay checkout directly in the Unity Editor without building to a device.

When you call OpenCheckout() in your scene, the extension automatically intercepts these calls and displays the flow in a window within Unity editor. This enables you to interact with the Stash Pay UI, complete purchases, and verify callback events directly in the editor.

Currently Windows and macOS versions of Unity are supported starting from Unity 2022.3.